The genus Morchella contains the species of mushrooms known as morels or sponge mushrooms. They belong to the ascomycetous fungi. True morels are edible and delicious. Indeed, some consider them the most delectable of all the fungi. While the taste of these mushrooms is known and loved by those who search the forests in the early spring, morels are unavailable to the general population because heretofore they have defied cultivation such as would be practical for commercial production year round.
To the connoisseur of mushrooms, morels are known by their ascocarp or fruitbody (the visible mushroom). One would suppose that if these fungi grow freely without cultivation in the wild or natural state, cultivation methods would have been developed to maximize their production. This, however, has not been the case. There are reports of growing morels outdoors; however, no one has succeeded in cultivating morels like the common Agaricus species or other edible forms in environmentally controlled rooms for harvesting throughout the year.
Ascocarp or fruitbody production is the mature embodiment of the sexual reproduction cycle of the morel. The mature ascocarp containing ascospores or germ spores represents the culmination of a life cycle highlighted by an internal mating of two haploid nuclei to form a diploid nucleus which undergoes meiosis to form new haploid ascospores. Both autogamous and heterogamous pairing prior to meiosis have been reported for Morchella. An alternative life cycle is an asexual process in which conidia (asexual spores) are produced and from which new mycelium, containing haploid nuclei, can be grown.
Also, as a means of protecting the species under certain conditions, the vegetative mycelia coalesce into hardened bodies known as sclerotia which may lie dormant during periods of unfavorable conditions. Accordingly, fruiting of the morel occurs during select conditions; a situation recognized by mushroom hunters who have experienced "bad years" for morel gathering.
It is a general object of the invention to provide a method for culturing morels in a manner suitable for commercial production of ascocarps throughout the year under controlled conditions.